Until relatively recently, telephone, television, and other communications services had been provided to homes, offices, and other consumers almost exclusively through copper-based cables. In these copper-based cables, the telephone, television, and other signals are transmitted along copper wires in the cable. Also until relatively recently, the cables associated with different services were provided separately to a consumer. For example, a household might have at one time had telephone service provided through a telephone cable and its television service provided through a separate coaxial cable. These services were commonly provided by different providers, such as a telephone utility and a cable television utility. With the advent of the internet and improvements in communications technology, however, these conventional telephone and coaxial cables are less commonly used. In their place, optical fiber cables have been used to provide both telephone and television services, as well as others.
In optical fiber cables, telephone, television, and other signals in the form of light pulses are transmitted along a core of material, such as glass, which is capable of transmitting light. Typically, a reflective coating known as cladding surrounds the core material so that light traveling along the core is internally reflected and propagates along the core. Optical fiber cables have proved to be useful for providing communications services, such as telephone, television, and internet services, and are becoming increasingly commonplace. For example, many modern households and offices now receive telephone, television, and internet services over optical fiber cables. In many cases, a single utility company provides all of these services over a single optical fiber cable. Thus, and because of the essential characteristics of an optical fiber cable, many consumers now have optical fiber cables providing a steady stream of light pulses into their homes or offices.
In another area of consumer technology, solar cells have been developed for converting light energy into electricity. Solar cells are also known as photovoltaic cells because they convert light to electricity according to the photovoltaic effect. In a well known arrangement, solar cells situated on top of a house or a building are positioned to receive sunlight. When the solar cells are exposed to sunlight, electricity is generated. This electricity can be captured and used to supplement, or in some cases replace, electricity from an electric utility. For example, the electricity generated by the solar cells can be used immediately or can be stored in a battery for later use. This reduces the amount of electricity that a consumer purchases from an electric utility. And in cases where excess electricity is generated by solar cells, the electricity can be sold back to the electric utility, which can then sell it to its other customers. Electric utilities currently generate most of the electricity that they sell by burning fossil fuels, such as coal. However, because fossil fuel supplies are limited and because burning fossil fuels is known to create undesirable byproducts, generating electricity by alternative means is currently receiving substantial attention.
There is a need, therefore, for devices and methods that generate electricity, but that do so without consumption of fossil fuels.